Dick Wirz

Dick Wirz

Tech Tips written:

Why the New Guy Gets Fewer Callbacks
I was going through a recorded service meeting with the Kalos techs, and Bert shared something that has been rattling around in my head ever since. His team went digging through their callback data looking for patterns, and after stepping back and looking at it, one showed up that nobody expected: The newer techs were […]
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Why is 240V called “Single-Phase”?
Why is it called single-phase 240 when there are two opposing phases (or legs)? I wondered why we called two 120v opposing legs “single-phase 240” for years. Then someone pointed out to me that a typical “single-phase” pole transformer only has one power leg entering and two coming out. That freaked me out. How can […]
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Flowing Nitrogen? Make Sure You Purged First
Flowing nitrogen while brazing does not mean the air was cleared first. Learn how to purge large ACR piping, choose a practical regulator setup, and estimate time and cylinder use.
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Podcast guest:

Commercial Refrigeration for A/C Techs w/ Dick Wirz (Podcast)
Dick Wirz, author of Commercial Refrigeration for Air Conditioning Technicians, talks about making the switch from A/C to refrigeration. Dick Wirz is an advocate for using rules of thumb, which is a controversial position. However, rules of thumb are an excellent way for A/C techs to dip their toes into the refrigeration world. Rules of […]
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